/*
 * (c) Copyright Ascensio System SIA 2010-2024
 *
 * This program is a free software product. You can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License (AGPL)
 * version 3 as published by the Free Software Foundation. In accordance with
 * Section 7(a) of the GNU AGPL its Section 15 shall be amended to the effect
 * that Ascensio System SIA expressly excludes the warranty of non-infringement
 * of any third-party rights.
 *
 * This program is distributed WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE. For
 * details, see the GNU AGPL at: http://www.gnu.org/licenses/agpl-3.0.html
 *
 * You can contact Ascensio System SIA at 20A-6 Ernesta Birznieka-Upish
 * street, Riga, Latvia, EU, LV-1050.
 *
 * The  interactive user interfaces in modified source and object code versions
 * of the Program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU AGPL version 3.
 *
 * Pursuant to Section 7(b) of the License you must retain the original Product
 * logo when distributing the program. Pursuant to Section 7(e) we decline to
 * grant you any rights under trademark law for use of our trademarks.
 *
 * All the Product's GUI elements, including illustrations and icon sets, as
 * well as technical writing content are licensed under the terms of the
 * Creative Commons Attribution-ShareAlike 4.0 International. See the License
 * terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode
 *
 */

'use strict';

const cluster = require('cluster');
const config = require('config').get('SpellChecker');

//process.env.NODE_ENV = config.get('server.mode');

const logger = require('./../../Common/sources/logger');

const c_nCheckHealth = 60000, c_sCheckWord = 'color', c_sCheckLang = 1033;
let idCheckInterval, canStartCheck = true;
let statusCheckHealth = true;

function checkHealth(worker) {
    logger.info('checkHealth');
    if (!statusCheckHealth) {
        logger.error('error check health, restart!');
        worker.kill();
        return;
    }
    worker.send({type: 'spell'});
    statusCheckHealth = false;
}

function endCheckHealth(msg) {
    logger.info('endCheckHealth');
    statusCheckHealth = true;
}

const workersCount = 1;	// ToDo So far, we will use only 1 process. But in the future it is worth considering a few.
if (cluster.isMaster) {
    logger.warn('start cluster with %s workers', workersCount);
    cluster.on('listening', function (worker) {
        if (canStartCheck) {
            canStartCheck = false;
            idCheckInterval = setInterval(function () {
                checkHealth(worker);
            }, c_nCheckHealth);
            worker.on('message', function (msg) {
                endCheckHealth(msg);
            });
        }
    });
    for (let nIndexWorker = 0; nIndexWorker < workersCount; ++nIndexWorker) {
        logger.warn('worker %s started.', cluster.fork().process.pid);
    }

    cluster.on('exit', (worker, code, signal) => {
        logger.warn('worker %s died (code = %s; signal = %s). restart...', worker.process.pid, code, signal);
        clearInterval(idCheckInterval);
        endCheckHealth();
        canStartCheck = true;
        cluster.fork();
    });
} else {
    const express = require('express'),
        http = require('http'),
        https = require('https'),
        fs = require("fs"),
        app = express(),
        spellCheck = require('./spellCheck');
    let server = null;


    logger.warn('Express server starting...');

    if (config.has('ssl')) {
        const privateKey = fs.readFileSync(config.get('ssl.key')).toString();
        const certificateKey = fs.readFileSync(config.get('ssl.cert')).toString();
        const trustedCertificate = fs.readFileSync(config.get('ssl.ca')).toString();
        //See detailed options format here: http://nodejs.org/api/tls.html#tls_tls_createserver_options_secureconnectionlistener
        const options = {key: privateKey, cert: certificateKey, ca: [trustedCertificate]};

        server = https.createServer(options, app);
    } else {
        server = http.createServer(app);
    }

    // If you want to use 'development' and 'production',
    // then with app.settings.env (https://github.com/strongloop/express/issues/936)
    // If error handling is needed, now it's like this https://github.com/expressjs/errorhandler	spellCheck.install(server, function(){
    server.listen(config.get('server.port'), function () {
        logger.warn("Express server listening on port %d in %s mode", config.get('server.port'), app.settings.env);
    });

    app.get('/index.html', function (req, res) {
        res.send('Server is functioning normally');
    });

    process.on('message', function (msg) {
        if (!spellCheck)
            return;
        spellCheck.spellSuggest(msg.type, c_sCheckWord, c_sCheckLang, function (res) {
            process.send({type: msg.type, res: res});
        });
    });

    process.on('uncaughtException', function (err) {
        logger.error((new Date).toUTCString() + ' uncaughtException:', err.message);
        logger.error(err.stack);
        logger.shutdown(function () {
            process.exit(1);
        });
    });
}
